Note 4 - Loans and Allowance for Loan Losses (Detail) - Allowance for Loan Losses Activity (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2012 Residential Portfolio Segment [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member]	Sep. 30, 2012 Residential Portfolio Segment [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member]	Sep. 30, 2012 Commercial Real Estate Portfolio Segment [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member]	Sep. 30, 2012 Commercial Real Estate Portfolio Segment [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member]	Sep. 30, 2012 Commercial and Industrial [Member]	Sep. 30, 2011 Commercial and Industrial [Member]	Sep. 30, 2012 Commercial and Industrial [Member]	Sep. 30, 2011 Commercial and Industrial [Member]	Sep. 30, 2012 Consumer Portfolio Segment [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member]	Sep. 30, 2012 Consumer Portfolio Segment [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member]	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Allowance for loan losses:
Beginning balance	$ 1,443	$ 1,133	$ 1,730	$ 1,051	$ 4,369	$ 3,392	$ 3,623	$ 3,083	$ 653	$ 770	$ 636	$ 3,795	$ 1,062	$ 1,184	$ 1,355	$ 1,457	$ 7,527	$ 6,479	$ 7,344	$ 9,386
Provision for loan losses	257	904	552	1,918	394	(82)	2,290	903	359	(74)	(48)	1,531	173	404	229	503	1,183	1,152	3,023	4,855
Loans charged off	(61)	(741)	(739)	(1,710)	(54)	(113)	(1,212)	(1,700)	(429)	(26)	(499)	(4,727)	(430)	(476)	(1,247)	(1,223)	(974)	(1,356)	(3,697)	(9,360)
Recoveries	23	59	119	96	27		35	911	159	48	653	119	240	129	708	504	449	236	1,515	1,630
Total ending allowance balance	$ 1,662	$ 1,355	$ 1,662	$ 1,355	$ 4,736	$ 3,197	$ 4,736	$ 3,197	$ 742	$ 718	$ 742	$ 718	$ 1,045	$ 1,241	$ 1,045	$ 1,241	$ 8,185	$ 6,511	$ 8,185	$ 6,511